Conventional bump process includes forming a photoresist layer on a substrate; performing exposure/develop process to pattern the photoresist layer; plating plural bumps on the patterned photoresist layer; eventually removing the patterned photoresist layer therefore completing the bump process. In the process of removing the photoresist layer, the substrate which covered by the photoresist layer is immersed into a photoresist stripping solution to make the photoresist layer generate imbibition and decomposition therefore stripping from the substrate. However, according to differed product demands, the types of photoresist materials and photoresist stripping solutions used in process are totally different. For the issue mentioned above, in the process of conventional photoresist strip, the time for immersing the substrate into the photoresist stripping solution is likely too long therefore causing dispersion of the bumps or damage of a protection layer of the substrate. Oppositely, once the time for immersing the substrate into the photoresist stripping solution is too short, the remaining of the photoresist layer is likely occurred therefore affecting the yield rate in the conventional bump process. In addition, the thicker bump in the bump process, the thicker photoresist layer is performing. The thicker photoresist layer need longer time for immersed into the photoresist stripping solution and more photoresist stripping solution for strip which increase the loading capacity of the environmental and producing cost.